Concentrated aqueous phytopathological formulation comprising a herbicide and a betaine type surfactant

ABSTRACT

The present invention concerns an aqueous phytopathological formulation comprising a hydrosoluble salt of at least one aminophosphate or aminophosphonate type herbicide; at least one principal surfactant selected from alkylbetaines and alkyl(amidoalkyl)betaines, and at least one additive selected from at least one of the following compounds:  
     (i) amines or etheramines comprising at least one hydrocarbon radical containing 2 to 24 carbon atoms, optionally polyalkoxylated;  
     (ii) acid or non acid phosphate mono- or di-esters, optionally polyalkoxylated;  
     (iii) alkali metal, alkaline-earth metal, ammonium, alkylammonium, alkanolammonium, iron, zinc or manganese salts of a mineral acid.

[0001] The present invention relates to aqueous phytopathologicalformulations comprising at least one aminophosphate or aminophosphonatetype herbicide and at least one betaine type principal surfactantassociated with one or more particular additives.

[0002] Among the various normal presentations of phytopathologicalformulations that can be cited are concentrated aqueous formulationswhich are diluted by the user prior to applying them to the plants to betreated.

[0003] In addition to the active ingredient or ingredients, such aqueousformulations comprise additives known as biological activators the roleof which is to increase the efficacy of the herbicide, for example byencouraging wetting of the plant by that active ingredient or byencouraging penetration into the plant.

[0004] Particularly regarding aqueous commercial formulations comprisingactive ingredients of the amino acid type cited above, one of the mostfrequently used biological activators is an ethoxylated amine.

[0005] The presence of these amines considerably strengthens thebiological activity of the herbicide, most probably by activatingdiffusion of the herbicide through the cuticular barrier of the plant.

[0006] The major disadvantage with ethoxylated amine compounds is theirchemical toxicity. They are irritants and are only slightlybiodegradable. Further, they are highly ecotoxic, more particularlytowards aquatic plant organisms (algae) or aquatic animals (insects,batrachia) even at low concentrations.

[0007] The ever more serious view taken of these different problems hasled to a search for phytopathological compounds, preferably hydrosolublephytopathological compounds, with a biological activity that iscomparable to current formulations and with substantially reducedtoxicity and ecotoxicity.

[0008] Thus, the present invention aims to provide novel aqueousphytopathological formulations comprising at least one activeingredient, more particular a herbicide of the aminophosphate oraminophosphonate type, with a proportion of ethoxylated amine withrespect to the herbicide that is lower than in the normal formulations,or even free of such amines, while retaining an activity that is atleast equal to said formulations.

[0009] These and other aims are accomplished by the present inventionwhich thus concerns aqueous phytopathological formulations comprising ahydrosoluble salt of at least one aminophosphate or aminophosphonatetype herbicide; at least one principal surfactant selected fromalkylbetaines and alkyl(amidoalkyl)betaines, and at least one additiveselected from at least one of the following compounds:

[0010] (i) amines or etheramines comprising at least one hydrocarbonradical containing 2 to 24 carbon atoms, optionally polyalkoxylated;

[0011] (ii) acid or non acid phosphate mono- or di-esters, optionallypolyalkoxylated;

[0012] (iii) alkali metal, alkaline-earth metal, ammonium,alkylammonium, alkanolammonium, iron, zinc or manganese salts of amineral acid.

[0013] The particular choice of principal surfactant combined with atleast one of the additives listed above can produce phytopathologicalformulations with a reduced ethoxylated amine content, or evenformulations that are free of this type of compound while retaining alevel of efficacy that is at least as good as that achieved withcommercially available formulations.

[0014] The consequences of this reduction in the amount of ethoxylatedamine are to be found in the significant reduction in the toxicity ofthe final formulation itself. These characteristics are still furtherimproved when the formulation is free of that amine.

[0015] Further, the formulation of the invention is stable on storageand does not cause problems during use. No gel appears, nor does theviscosity increase greatly during dilution prior to application.

[0016] Other advantages and characteristics of the present inventionwill become apparent from the following description and examples.

[0017] As indicated above, the formulation of the invention comprises,as an active ingredient, a hydrosoluble salt of at least one herbicideof the aminophosphate or aminophosphonate type.

[0018] Preferably, the formulations of the invention comprise at leastone hydrosoluble salt of N-phosphonomethyl glycine.

[0019] The term “glyphosate” will be used below to define hydrosolublesalts of N-phosphonomethyl glycine.

[0020] Suitable salts that can more particularly be cited are the saltsof alkali metals such as sodium or potassium; ammonium salts of theN(R)₄ ⁺ type in which radicals R, which may be identical or different,represent a hydrogen atom or a linear or non linear, saturated orunsaturated C₁-C₆ hydrocarbon radical that may be substituted by ahydroxyl group; or sulphonium salts; said salts being present alone orin a combination.

[0021] Ammonium salts that can in particular be cited include secondaryor primary amines such as isopropylamine, dimethylamine, diamines suchas ethylenediamine, or alkanolamines such as monoethanolamine.Trimethylsulphonium is a perfectly suitable sulphonium salt.

[0022] Preferred glyphosate derivatives for herbicidal application thatcan be cited are isopropylamine, the monoethanolamine salt and thetrimethylsulphonium salt.

[0023] Advantageously, the herbicide content of the aqueous formulationsof the invention is in the range 80 to 510 g/l expressed in acidherbicide equivalents.

[0024] In accordance with one essential feature of the invention, theaqueous formulations comprises at least one principal surfactantselected from alkylbetaines and alkyl(amidoalkyl)betaines.

[0025] Preferably, the principal surfactant corresponds to one or moreof the following formulae:

[0026] in which formulae:

[0027] R¹ represents a linear or branched alkyl group containing 3 to 30carbon atoms, preferably 3 to 20 carbon atoms, such as propyl, dodecyl,hexadecyl or an alkamide group, such as dodecanamide;

[0028] R², which may or may not be identical, represent an alkylradical, preferably a methyl radical;

[0029] R³ represents a hydrogen atom or a —CH₂COOM radical or an alkylradical;

[0030] M represents an alkali metal, preferably sodium.

[0031] Said compounds, which can be used in the invention as principalsurfactants, are commercially available products and are sold by RhodiaChimie under the trade names Mirataine® and Wettem®. Advantageously,said commercially available products can be used as they are, withoutundergoing an initial treatment to reduce the amount of salt, forexample (sodium chloride in particular).

[0032] The amount of principal surfactant in the phytopathologicalformulation of the invention is advantageously in the range 20 to 180g/l.

[0033] In addition to the principal surfactant, the phytopathologicalformulations of the invention comprise at least one additive selectedfrom at least one of the following compounds:

[0034] (i) amines or etheramines comprising at least one hydrocarbonradical containing 2 to 24 carbon atoms, optionally polyalkoxylated;

[0035] (ii) acid or non acid mono- and di-ester phosphates, optionallypolyalkoxylated;

[0036] (iii) alkali metal, alkaline-earth metal, ammonium,alkylammonium, alkanolammonium, iron, zinc or manganese salts of amineral acid.

[0037] In accordance with a first possibility, compounds (i) are moreparticularly selected from amines comprising at least one linear orbranched, saturated or unsaturated radical containing 2 to 24 carbonatoms, preferably 8 to 18 carbon atoms, optionally comprising 2 to 30oxyalkylene motifs, preferably oxyethylene, or a mixture of a pluralitythereof.

[0038] In accordance with a second possibility, compounds (i) areselected from etheramines comprising at least one linear or branched,saturated or unsaturated radical containing 6 to 24 carbon atoms,preferably 8 to 20 carbon atoms, optionally comprising 2 to 30oxyalkylene motifs, preferably oxyethylene, or a mixture of a pluralitythereof. More particularly, the etheramines correspond to the followingformula:

[0039] in which formula R represents a linear or branched, saturated orunsaturated hydrocarbon radical containing 6 to 24 carbon atoms,preferably 8 to 20 carbon atoms; OA, which may or may not be identicalfrom one motif to another and from one branch to another, represent anoxyethylene motif, preferably oxypropylene; and n, n′, which may or maynot be identical, represent a mean number in the range 1 to 30.

[0040] Examples of such amines that can be cited are amines derived fromcopra and containing 5 oxyethylene (OE) motifs, oleic amines containing5 OE, amines derived from tallow containing 10 OE, etheraminescorresponding to the above formula, in which radical R is an alkylradical containing 12 to 15 carbon atoms, the number of OE motifs beingin the range 20 to 30.

[0041] It should be noted that highly advantageously, the amount ofcompounds (i) represents 0 to 120 g/l of the formulation. In aparticular implementation of the invention, the amount of this type ofcompound is in the range 0 to 60 g/l. Preferably, the phytopathologicalformulations are free of them.

[0042] Turning now to compounds (ii), these are preferably selected fromacid or non acid phosphate mono- or di-esters, optionallypolyalkoxylated, with formula (II) below:

(AO)_(3-m)P(═O)(OM)_(m)

[0043] in which:

[0044] A, which may or may not be identical, represent a groupR′¹—O(CH₂—CHR′²—O) in which:

[0045] R′¹, which may or may not be identical, represent a linear or nonlinear, saturated or unsaturated C₆-C₂₀ hydrocarbon radical, preferablyC₈-C₁₈;

[0046] R′², which may or may not be identical, represent a hydrogen atomor a methyl or ethyl radical, preferably a hydrogen atom;

[0047] n is a mean number of motifs in the range 0 to 10, preferably inthe range 2 to 10;

[0048] M, which may or may not be identical, represent a hydrogen atom,an alkali or alkaline-earth metal, a N(R³)₄ ⁺ type radical in whichradicals R³, which may or may not be identical, represent a hydrogenatom or a linear or non linear, saturated or unsaturated C₁-C₆hydrocarbon radical optionally substituted with a hydroxyl group;

[0049] m is a whole number in the range 1 to 2.

[0050] It should be noted that compound (ii) can be in the form of amonoester, a diester, or a mixture of these two esters.

[0051] Further, the amount of compound (ii), if present in theformulation of the invention, is in the range 0 to 120 g/l.

[0052] Compound (iii) is advantageously selected from alkali metal oralkaline-earth metal, ammonium, or linear or non linear, saturated orunsaturated C₁-C₆ alkylammorium or alkanolammonium sulphates, nitratesor phosphates; or from iron, zinc or manganese sulphates, used alone oras a mixture.

[0053] Finally, the amount of compound (iii) in the formulations, ifpresent, is more particularly in the range 0 to 200 g/l.

[0054] In accordance with a preferred characteristic of the invention,the proportion by weight of principal surfactant/sum of additives (i) to(iii) is in the range 6/1 to 1/2.

[0055] Further, in one implementation of the invention, the total amountof principal surfactant and additive(s) represents 60 to 180 g/l of theformulation.

[0056] The formulations can also comprise additives that areconventional in the field such as anti-foaming agents, for exampleorganopolysiloxanes; or thickening agents such as xanthan gum typepolysaccharides, alginates, carboxylated or hydroxylatedmethylcelluloses, synthetic macromolecules of the polyacrylate,polymaleate, polyvinylpyrrolidone, polyethylene glycol or polyvinylalcohol type, or of the inorganic type such as bentonites.

[0057] The formulation can also comprise auxiliary additives such asantioxidants, anti-UV agents, colorants, etc.

[0058] The amount of these additives listed above is normally less than10% by weight, preferably 1% by weight or less, advantageously 0.1% byweight or less compared with the composition weight.

[0059] The compositions of the invention can be prepared by mixing theirdifferent constituents with moderate stirring.

[0060] This operation preferably takes place at a temperature in therange 15° C. to 60° C., preferably at a temperature close to ambienttemperature (15-30° C.).

[0061] Usually, the principal surfactant is preferably only added oncethe other constituents have been mixed.

[0062] The phytopathological formulations of the invention are thus usedto treat plants, normally after diluting with water.

[0063] Non-limiting examples of the invention will now be described.

EXAMPLE 1

[0064] A mixture with the following composition was prepared in water:*glycosphosate isopropylamine salt (46% acid) 360 g/l *Mirataine ®D40(*)  80 g/l *Geronol ® CF/AR (**)  20 g/l *oleic amine containing 5OE motifs  20 g/l

[0065] A composition was obtained the efficacy of which was equivalentto a composition comprising the same amount of glyphosate (expressed asthe acid equivalent) and with a concentration of 180 g/l of ethoxylatedoleic amine (15 motifs).

[0066] The formulation was stable on storage at ambient temperature andat 54° C.

EXAMPLE 2

[0067] A mixture with the following composition was prepared in water:*glycophsate isopropylamine salt (46% acid) 360 g/l *Wettem ® MEI(*) 100g/l *ammonium sulphate  19 g/l

[0068] A composition was obtained the efficacy of which was equivalentto a composition comprising the same amount of glyphosate (expressed asthe acid equivalent) and with a concentration of 180 g/l of ethoxylatedoleic amine (15 motifs).

[0069] The formulation was stable on storage at ambient temperature andat 54° C.

1-13. (canceled).
 14. An aqueous phytopathological formulationcomprising: a hydrosoluble salt of at least one aminophosphate oraminophosphonate herbicide, wherein the herbicide content is comprisedbetween 80 and 510 g/l, expressed in acid herbicide equivalents, between20 and 180 g/l of at least one principal surfactant alkylbetaine, havingformula (I): R¹R²R²N⁺—CH₂COO⁻ wherein: R¹ represents a linear orbranched alkyl group containing 3 to 30 carbon atoms or an alkamidegroup, and R², which is identical or different, represents an alkylgroup, and from 0 excluded to 120 g/l of one or more additive (i) beinga polyalkoxylated amine having at least one hydrocarbon group containingfrom 2 to 24 carbon atoms.
 15. A formulation according to claim 14,wherein the herbicide is a hydrosoluble salt of N-phosphonomethylglycine.
 16. A formulation according to claim 14, wherein: R¹ representsdodecyl, or hexadecyl, and R² represents methyl.
 17. A formulationaccording to claim 14, wherein the additive (i), used alone or as amixture, has at least one linear or branched, saturated or unsaturatedgroup containing 8 to 18 carbon atoms, and presents 2 to 30 oxyalkylenemotifs.
 18. A formulation according to claim 17, wherein the oxyalkylenemotifs are oxyethylene motifs.
 19. A formulation according to claim 18,wherein additive (i), is an amine derived from tallow, containing 10oxyethylene motifs.
 20. A formulation according to claim 18, wherein R¹represents dodecyl, or hexadecyl, and R² represents methyl.
 21. Aformulation according to claim 14, comprising from from 0 excluded to 60g/l of additive (i).
 22. A formulation according to claim 20, comprisingfrom from 0 excluded to 60 g/l of additive (i).
 23. A formulationaccording to claim 14, wherein the ratio by weight of principalsurfactant/sum of additive (i), is comprised between 6/1 to 1/2.
 23. Aformulation according to claim 20, wherein the ratio by weight ofprincipal surfactant/sum of additive (i), is comprised between 6/1 to1/2.
 24. A formulation according to claim 22, wherein the ratio byweight of principal surfactant/sum of additive (i), is comprised between6/1 to 1/2.
 25. A formulation according to claim 14, wherein the totalamount of principal surfactant and additive (i), represents from 60 to180 g/l of the formulation.
 26. A formulation according to claim 24,wherein the total amount of principal surfactant and additive (i),represents from 60 to 180 g/l of the formulation.
 27. A formulationaccording to claim 26, wherein the herbicide is a hydrosoluble salt ofN-phosphonomethyl glycine.